1. Technical Field
This disclosure generally relates to an image processing apparatus, an image processing method, and a program product for executing the method in which an image synthesizing function is provided.
2. Description of the Related Art
By development of an image reading device which uses a line sensor formed of a CCD (charge coupled device) (photoelectric conversion element), and a toner image writing device which irradiates laser beams on a photoconductor body, digital copiers have been made available in the market place in which a document is copied by converting analog image data into digital image data.
Since the digital image data are used, not only the digital copiers, but MFPs (multifunctional peripherals) have been made available in the market place in which various functions such as a copying function, a facsimile function, a printing function, and an image scanning function are integrated.
Recently, the throughput of CPUs (central processing units) has been increasing, the capacity of storage units such as HDDs (hard disk drives) has been increasing, the manufacturing cost of storage units has been decreasing, high-speed operations in communication networks have been realized, and digital technologies such as a compression technology for digital image data have been developed. With these developments, many functions have been installed in the MFPs.
In addition, corresponding to changes of the office environment where the MFPs are used, various types of MFPs have been developed to meet the demands for use of the MFPs.
For example, a small-type MFP is used with a PC (personal computer) in an office so that a user can easily use functions such as a copying function, a facsimile function, a printing function, and an image scanning function; a middle-type MFP is used in common by plural persons in an office so that productivity in the office is increased by using functions such as a document sorting function, a document punching function, and a document stapling function with the above described functions; and a large-type MFP is used in a department so that jobs related to document copying are centralized or in a company whose business is copying documents so that the multiple functions are performed with high productivity in forming high quality images.
In order to satisfy the demands in the market place, in each of the MFPs, a system having necessary functions has been developed, and an MFP having the developed system has been offered to users.
The importance of information has been long recognized in business. In an apparatus including an MFP which processes information, the apparatus has been required to have functions to provide the information effectively and clearly in addition to providing the information accurately and quickly.
In an apparatus which handles information, the apparatus has been required to have a new function which effectively and clearly handles information by using digital data. Even in the MFP market place, a new type MFP has been required in which information can be effectively and clearly processed by utilizing digital data.
As one of the functions, image data of a document read by a reading function of an MFP is stored in a storage unit, and when a user requests the image data, the image data are output.
When the image data stored in the storage unit are output, in many cases, time has passed from storing the image data to outputting the image data, and a request of the user for outputting the image data may be changed.
In Patent Document 1, an image processing apparatus is disclosed. In the image processing apparatus, a distinctive part of a document is extracted, processes such as a filtering process and a color correcting process are applied to image data of the document based on an extracted result, and the image data of the document and an identification signal showing the distinctive part of the image data are stored in an HDD. When a user requests to output the image data, an image process corresponding to the request of the user is executed based on the requirement of the user.    [Patent Document 1] Japanese Patent No. 3647347 (Japanese Laid-Open Patent Application No. 2001-223828)
However, in Patent Document 1, the stored image data depend on an input characteristic of an image reading device of the image processing apparatus. When the image data are shared with other apparatuses, the input characteristic of the image reading device must be transmitted to the other apparatuses, with the image data which the apparatus desires to share, as a profile. Consequently, the processes becomes complex.
In addition, in Patent Document 1, in a case where an irreversible data compression technology (for example, a technology in JPEG (Joint Photographic Experts Group) is used for storing the image data, when the document is formed of halftone dots, the compression rate is lowered, and an unintended moire pattern is generated. Consequently, in some cases, image quality may be extremely degraded.
In addition, in a case where the compression rate is lowered by noise and there are remaining white background data when the document is read, and in a case where the compression rate is lowered when the document is formed of the halftone dots, the processing speed for the image data is lowered and a large region for storing the image data is required.
There is a method which solves the above problems. In the method, an image region separating process is applied to image data before the image data are stored, from separated image regions, only image regions having image distinctive data, which are necessary when an image process is applied to the image data, are converted into predetermined signals, and from the converted signals, image distinctive data are generated. Then a most suitable image process is applied to the image data based on the image distinctive data.
In the above method, degradation of image quality is prevented and using the large region for storing the image data is avoided. However, when the image data input from the image reading device in the MFP and image data input from an external apparatus (for example, an information processing apparatus, an external recording medium, or an external image processing apparatus) are stored in a storage unit and the stored image data are output by synthesizing the stored image data, since suitable synthesized image distinctive data are not generated for the synthesized image data, a suitable image process cannot be applied to the synthesized image data. Consequently, unintended image data may be output.